1. Field of the Invention
This invention pertains to a high precision drive mechanism for transmission of power and/or motion from an input shaft to an output shaft, which also may be used for moving objects to a predetermined position or angular orientation with high precision.
2. Description of the Prior Art
Drive components to transmit power and motion are necessary almost on every machine. Well-known chain drives, gears and flexible belt drives are used throughout the industry. Each of the above drives has advantages over another depending on the application.
Gear drives are expensive with demands for high precision, zero backlash and silence. They do not provide as smooth a transmission of motion as belt drives. Disadvantages of belt drives include the needed tensioning of the belts periodically to avoid slippage; deterioration because of severe exposure to chemicals and lubricants; and the requirement that damaged belts must be replaced rather than repaired. Conventional belts cannot be used where input and output shafts must be synchronized. Synchronous timing belts have relatively high cost and demand a fairly accurate alignment of pulleys.
Furthermore, inherently, prior art belt or chain drive mechanisms impose certain restrictions on the orientation of their pulleys and on the distances between the shafts thereof.